Merge branch 'master' into cairocanvas

diff --combined libs/backends/jack/jack_audiobackend.cc
index d45719036f3146c1ad56e25f6863cf785cc2bbb4,332b6eec8595ccaca8ffe198905bf91d7176a2bd..ccd80e2e84e6bbb84fadd5075dcbde14507e01d9
--- 1/libs/backends/jack/jack_audiobackend.cc
--- 2/libs/backends/jack/jack_audiobackend.cc
+++ b/libs/backends/jack/jack_audiobackend.cc
@@@ -547,8 -547,11 +547,11 @@@ JACKAudioBackend::_start (bool for_late
        /* Now that we have buffer size and sample rate established, the engine 
           can go ahead and do its stuff
        */
-       
-       engine.reestablish_ports ();
+ 
+       if (engine.reestablish_ports ()) {
+               error << _("Could not re-establish ports after connecting to JACK") << endmsg;
+               return -1;
+       }
  
        if (!jack_port_type_get_buffer_size) {
                warning << _("This version of JACK is old - you should upgrade to a newer version that supports jack_port_type_get_buffer_size()") << endmsg;
@@@ -764,6 -767,9 +767,6 @@@ JACKAudioBackend::jack_sync_callback (j
        TransportState tstate;
  
        switch (state) {
 -      case JackTransportStopped:
 -              tstate = TransportStopped;
 -              break;
        case JackTransportRolling:
                tstate = TransportRolling;
                break;
@@@ -773,10 -779,6 +776,10 @@@
        case JackTransportStarting:
                tstate = TransportStarting;
                break;
 +      case JackTransportStopped:
 +      default:
 +              tstate = TransportStopped;
 +              break;
        }
  
        return engine.sync_callback (tstate, pos->frame);